Among the semiconductor device manufacturing processes, an ion implantation process is used to perform doping on a display panel, a semiconductor wafer or other work pieces. Doping is often performed on a substrate, and various expected effects on the substrate may be achieved by implanting a certain type of ions therein to change the diffusion capability of a dielectric layer of the substrate.
In a practical application, an ion implantation process is performed in batches, that is, a plurality of substrates are implanted simultaneously or implanted in batches. When a plurality of substrates or a plurality of batches of substrates are processed in this manner, the ion implantation apparatus is required to continuously generate uniform and stable ion beam.
However, when a large batches of substrates are processed by using a conventional ion implantation apparatus, the stability and uniformity of the ion beam are always changed, that is, when different batches of substrates are processed, there are remarkable difference in the stability and uniformity of the ion beam, thus performance uniformity of the processed base materials in each batch or among various batches cannot be ensured. The stability and uniformity of ion implantation have become a problem to be solved urgently in the current semiconductor process. In the prior art, in order to solve the problem in stability of ion implantation, a common method used is to improve the structure of the apparatus, however, this method causes a high cost, and the stability of ion implantation is still low.